The present invention relates to a valve system connectable to a fluid channel, wherein the valve system comprises an actuating means and a closing element for selectively closing and opening of the channel.
Fluid channels in the form of discharging extensions may be connected to fluid containers such as tubes, bottles, barrels, tanks or bags. In many cases the fluid container and/or the fluid channel are connected to a closing mechanism such as a sealing lid to prevent evaporation, leakage or a contamination caused by a contact between the fluid and the outer atmosphere during storage. However, during discharging of the fluid most of the known fluid containers do not prevent a contact between the fluid in the container and air or they even support the intrusion of air.
However, in specific applications it is very important that the fluid contained in the container does not get in contact with the outer atmosphere at all. This may for example be the case for certain medical products, sterile solutions, pharmaceutical products, fungicides, antibacterials, disinfectants, preservative agents, hygiene products, sanitary products or industrial processing products such as drugged oil, lubricants or cooling agents. For many of such fluid products a small contamination with air may have already a negative influence on the fluid quality and the applicability of the fluid for its intended use. Especially for manually manageable fluid containers which may be spatially oriented in any direction, i.e. in an upright storage position, an upside-down discharging position or any position in between, a special valve system is required to provide the possibility to discharge the fluid without letting air into the container.
In order to prevent an inflow of air through the opening of a compressible fluid container such as a collapsible tube before, during and after discharging of fluid, EP 1 772 392 A2 describes a valve system having a closing member with a resilient portion such that the closing member is capable of being deformed in a direction of an outward fluid flow caused by an excess pressure in the container. As soon as the outward fluid flow stops the resilient portion of the closing member closes the opening such that no air may enter the container. The elastic resilience of the tube material causes an under pressure in the container such that the closing member is further pressed into a sealing position to close the opening.
This design has several disadvantages. Firstly, for discharging fluid it is necessary to manually compress the collapsible tube container in order to produce the required excess pressure in the container. An automatic outflow of the fluid under its gravitational force alone is not possible. Secondly, due to the elastic stiffness of the resilient tube material there is a constant under pressure present during storage of the fluid in the container. A tiny or creeping leakage will therefore result in an inward flow of air contaminating the fluid. Thirdly, the valve system may open in any spatial orientation of the container. This is a potential risk for accidental opening in an undesirable position. A desired spatial orientation of the container for discharging the fluid may for instance be an upside down orientation in which the opening is located below the fluid level. A discharging in any other orientation may be undesirable. The valve system described in the EP 1 772 392 A2 works independently of the spatial orientation of the container and therefore poses a risk of accidental opening in an undesirable orientation.